State accident investigators probing Tuesday’s fatal crash of a rescue helicopter at Sollihøgda near Oslo have confirmed that it ran into a high-voltage power line at a height of just 20-30 meters, and that caused it to plunge to the ground. Questions remain as to why the pilot hit the lines, but there were communications problems between him and police on the ground.
Preliminary results of the investigation by the state accidents review board Havarikomisjonen show that the helicopter hit the power lines in several places. One of the power lines wrapped itself around the helicopter’s main rotary, causing the pilot to lose control.
There’s been debate between utility companies and the aviation industry over how power lines should be marked for safety reasons. Norwegian Broadcasting (NRK) reported that those running along the ridge at Sollihøgda where the fatal crash occurred were registered within the air ambulance service’s own mapping database, according to Norsk Luftambulance’s chief of pilots.
“We still don’t know why the helicopter got tangled in the lines, and that’s what we’re working further with now,” Tor Nørstegård of the accident investigation board told NRK on Thursday.
He said he and his colleagues will be questioning witnesses and studying film clips of the accident. They also will monitor relevant communications in the period before the accident occurred.
The helicopter was on its way to aid the driver of an overturned truck on slippery roads at Sollihøgda, where police and other emergency crews were already on the scene, when it became subject to a fatal accident itself. Police from the Northern Buskerud Police District claim they had cleared an area for the helicopter to land that they thought would be visible for the pilot, but said they had problems communicating verbally with him. They didn’t get a chance to warn the pilot about the nearby power lines.
Newspaper Aftenposten reported that just before the crash occurred, there was communication between the helicopter’s emergency crew and an ambulance on the ground, but it took place over another frequency that neither the police nor fire fighters at the scene had on their radios.
Neither the police, health care workers nor fire fighters in Nordre Buskerud have taken the state’s new digital emergency network into use yet. It’s not the first time emergency communications have become an issue in Norway, and accident investigators were working to sort out what went wrong on Tuesday.
Two of the three men on board the helicopter were killed including the pilot Bjørn Nergård, age 52, and the doctor, Anders Rostrup Nakstad, age 38. The third emergency worker on board, 51-year-old Sondre Bratland, remained in serious but stable condition at Oslo University Hospital on Thursday.